Tubes for microscopes have been known for some time from the existing art. Reference is made, purely by way of example, to U.S. patent application Ser. No. 2001/00 30 801 A1, from which a tube for a microscope is known. This tube is a so-called ergonomic tube, namely one in which the operator interface—the portion of the tube, usually the eyepieces, facing toward an operator's eyes—is arranged rotatably. The rotatable arrangement of the operator interface makes possible an individual adaptation of the tube to an operator of the microscope in such a way that, for example, the eyepieces of the tube can be moved on a circular arc. The viewing height into the microscope tube can thereby be adjusted, a change in the horizontal eyepiece position being simultaneously accompanied, because of the rotatably arranged operator interface, by a change in the vertical eyepiece position.
Each microscope operator usually assumes a position with respect to the microscope that is acceptable to him or her. For example, the spacing of some microscope operators from the microscope is relatively small, but the spacing of other microscope operators from the microscope is relatively large in comparison thereto. This can depend, inter alia, on the microscope operator's arm length. A microscope operator can vary the viewing height using the microscope tube known from U.S. patent application no. 2001/00 30 801 A1, but the viewing angle for the operator also simultaneously changes, so that the operator must tilt his or her head differently for different rotation angle positions of the operator interface. There is thus only a very limited possibility for working ergonomically with the microscope. With the microscope tube known from U.S. patent application no. 001/00 30 801 A1, it is not possible to vary the spacing from the microscope to the operator without varying the viewing angle.